An earphone is a converting unit that receives electrical signals from a media player or a receiver and converts them into audible sound waves using speakers that are proximate to the ears. Conventionally, there are only pure sports earphones or traditional in-ear earphones. The conventional earphones cannot be used during certain sports, such as swimming, and are easily damaged. To enhance entertainment during certain sports, it is desirable to design an earphone that is suitable for water and underwater sports, or other environments where the earphones could be exposed to liquids.